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FIELD OF INVENTION
The present invention relates to Desalination plant, which is water purification
plant to remove the excess salt and other minerals from water in order to obtain
clean water. More particularly this invention relates to a system, which monitors
the Desalination plant from remote using cellular telecommunication network.
BACKGROUND OF THE INVENTION
Desalination is a process that removes dissolved minerals (including but not
limited to salt) from seawater, brackish water, or treated wastewater. A number
of technologies have been developed for desalination, including reverse osmosis
(hereafter referred to as RO), distillation, electro-dialysis, and vacuum freezing.
In RO, feedwater is pumped at high pressure through semi-permeable
membranes, separating salts from the water. The feedwater is pretreated to
remove particles that would clog the membranes. The quality of the water
produced depends on the feed pressure, temperature of feed water, the
concentration of salts in the feedwater, and the salt permeation constant of the
membranes. Product water quality can be improved by adding a second pass of
membranes, whereby product water from the first pass is fed to the second
pass. To maintain the quality of water the critical parameters of the desalination
operation are monitored with a PLC. Some of the parameters include feedwater
pH, feedwater temperature, feedwater conductivity, oxygen reduction potential
(ORP), high-pressure pump suction pressure, high-pressure pump discharge
pressure, membrane inlet pressure, inlet conductivity and permeate conductivity.

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Each parameter are configured to a set value or to a set band for the operation
of plant. The plant is allowed to operate within set values/band and shutdown
once operating parameters crosses the band or limit.
OB3ECTS OF THE INVENTION
It is therefore an object of the invention to propose a system for remote
monitoring of desalination plant using cellular telecommunication network.
Another object of the invention is to propose a system for remote monitoring of
desalination plant using cellular telecommunication network, which is enabled for
multiple type of communications namely, SMS communication through cellular
network, serving web pages through GPRS using cellular network, serving web
pages in local area network (LAN), analog signal interface and digital signal
interface, for remote monitoring of desalination plant operation.
A still another object of the invention is to propose a system for remote
monitoring of desalination plant using cellular telecommunication network, which
provides for dynamic selection of the desalination plant operating parameters,
which are to be acquired from the Programmable Logic Controller (PLC) of the
plant.
Yet another object of the invention is to propose a system for remote monitoring
of desalination plant using cellular telecommunication network, which is capable
to perform high-speed data acquisition of the desalination plant operating
parameters.

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A further object of the invention is to propose a system for remote monitoring of
desalination plant using cellular telecommunication network, which is capable of
presenting multiple operating parameters that include feedwater pH, feedwater
temperature, feedwater conductivity, oxygen reduction potential (ORP), high-
pressure pump suction pressure, high-pressure pump discharge pressure,
membrane inlet pressure, inlet conductivity and permeate conductivity of the
desalination plant through SMS.
A still further object of the invention is to propose a system for remote
monitoring of desalination plant using cellular telecommunication network, which
is enabled to transmit the operating parameters of the desalination plant through
a web-interface accessable through both GPRS communication network and
through Local Area Network (LAN).
SUMMARY OF THE INVENTION
The present invention provides a system for remote monitoring of desalination
plant using cellular network. The invented system comprises hardware for
acquiring and subsequent processing of desalination plant operating parameters
from the PLC of the desalination plant .The invented system further comprises a
GSM/GPRS modem to transmit the message/data through cellular network.
The present invention utilizes a core module and peripheral components for
implementing the hardware. The core module is an intelligent processor based
printed circuit board having communication channel, digital input-output and
memory.

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The system has hardware circuit and the associated software to perform
modbusRTU communication over RS-485. The system communicates with the
PLC through modbusRTU protocol over RS-485 using predefined set of
commands. The status of the critical and necessary parameters is obtained from
the PLC. Some of the parameters include feedwater pH, feedwater temperature,
feedwater conductivity, oxygen reduction potential (ORP), high-pressure pump
suction pressure, high-pressure pump discharge pressure, membrane inlet
pressure, inlet conductivity and permeate conductivity.
The system has hardware circuit and the associated software to perform SMS
communication and to serve web pages through GPRS using cellular network.
The user can request for information from the system by sending a SMS through
cellular network. The system communicates with the cellular network through
the GSM modem. The SMS received through the cellular network are decoded
and the necessary information is collected from the PLC system. The acquired
data/status is suitably arranged as SMS frames and are sent back to the user
through the cellular network.
The system has hardware circuit and the associated software to perform
Ethernet network communication. The system has the capabilities to serve web
pages that present the operating parameters. The web pages can be viewed
over the LAN using web browsers.
The system has hardware circuit and the associated software to perform high-
speed data acquisition, both analog and digital.

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The system has the capability to serve web pages through general packet radio
service (hereafter referred to as GPRS). The system is also capable of sending
and receiving of short messaging service (hereafter referred to as SMS), thus
facilitating the monitoring of desalination plant from remote location. The system
is also capable of performing high-speed data acquisition, of both analog and
digital parameters. The system consists of the hardware to communicate with
the PLC, and the GSM modem interface to communicate with the cellular
network.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Figure 1 is a hardware block diagram of the system according to the invention.
Figure 2 is a software logic diagram of the system of the invention.
Figure 3 Illustrative Interface diagram of the system with the PLC of desalination
plant
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE
INVENTION
The hardware block diagram of the system for monitoring desalination plant is
shown in Figure 1.

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In the system, hardware block diagram the block (01) is the core module based
processor.
Blocks (2),(3) represent respectively the hardware for transmitting and receiving
of data through RS232 serial communication port. Block (4) indicates the
hardware for GSM modem. Blocks (5), and (6) indicate the RS-485 serial
communication interface to PLC hardware.
The block (02) has the hardware circuit for RS-232 communication. A GSM
modem (4) hardware is connected to the block (03) via a first port and then to a
transreceiver circuit of the block (2).
The processor (1) converts the SMS frame received from the GSM modem (4)
into required protocol format.
The block (05) has the hardware circuit for RS-485 communication. The PLC (21)
with modbusRTU communication protocol are connected to the block (05) via
second port and then to a second receiver circuit of the block (06). The
processor converts the modbusRTU frame into SMS frame.
A block (07) has the Ethernet port for Ethernet communication and serves
desalination plant operating parameters through a web-interface.
Figure 2 shows the logic diagram of the software.

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Software logic is shown in a block (16) which comprises a main block (09),
communication driver blocks (11, 13), communication protocol conversion blocks
(10,12).
The main block (09) initializes the default values and initiates the various tasks to
be performed during the operation.
The first communication driver block (11) receives and transmits SMS protocol
based message/data frames, and the second communication driver block (13)
receives and transmits modbusRTU protocol based data frames.
An Ethernet block (14) construct and serves the web pages, that present the
necessary/critical parameters. A block (15) represents the Ethernet port
Figure 3. Illustrates the interface of the system with the PLC (21) of the
desalination plant (31). The system transmits the status in SMS format to a
remotely located Personal Computer based system(30) or to a mobile phone(29).
In the desalination plant (31), a the feedwater pumped into a pretreatment plant
(17) for cleaning sediment particles and unwanted chemical with different
processes and chemical dose. Further the pretreated water is passed through a
Reverse Osmosis section (18) at higher pressure, which produces permeate
water having low dissolved solids (19) and brine (20) containing high dissolved
solids.

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The operation of the plant (31) is monitored locally by the PLCs (21). The set
value/band of the critical parameters of the desalination plant are configured
during installation. The system (23, 27) communicates to the PLC through
modbusRTU-based protocol over a RS485 bus (22). An analog interface (24) and
a digital interface (25) assigned to the plant parameters are scanned at high
speed. The Ethernet communication (26) serves the web pages. The system (23,
27) consists of processing & interfacing hardware and GSM modem. The status
frame in SMS format is constructed and transmitted by GSM modem to a cellular
network service provider (28). The SMS is received at the mobile phone (29) or
PC system (30).

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WE CLAIM
1. A system for remote monitoring of desalination plant in a cellular
telecommunication network, comprising:
- a core module based sub-system (08) comprising:
(i) means (2,3) for transmitting and receiving data through
RS 232 serial communication port, a GSM modem (4)
being connected to the means for (2,3) transmitting
and receiving, the processor (1) converting SMS frame
received from the GSM modem (4) into required
protocol format to perform SMS communication via the
cellular network;
(ii) means for (05, 06) RS-485 communication with the PLC
(21) of the desalination plant over a RS-485 bus (22),
the PLC (21) communicating with modbus RTU
communication ptotocol, the processor (1) converting
the modbus RTU frame into SMS frame;
(iii) means for (07) Ethernet communication (26) which
serves the operating parameters of the desalination
plant (31) through a web interface;

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- a software support structure (16) comprising a main block (9) for
initialization of the default values including the tasks to be
performed during the operation; at least two communication driver
blocks (11,13), the first driver (11) receiving and transmitting SMS
protocol based messages and/or data frames, the second driver
(13) receiving and transmitting modbus RTU protocol based data
frames; at least two communication protocol conversion blocks
(10,12); and an ethernet block (14) including an Ethernet port (15)
for constructing and serving the web pages through GPRS via the
cellular network; and
- a device (24, 25) for interfacing the PLC (21) of the desaliration
plant (31) and the system.

2. The system as claimed in claim 1, wherein the device for interfacing
comprises an analog interface (24), and a digital interface (25) to perform
high-speed data acquisition.
3. The system as claimed in claim 1, wherein the status frame in SMS format
is constructed and transmitted by the GSM modem (4) to a cellular
network service provider (28) which is further transmitted to a mobile
phone user (29) or a PC - system (30) located at a remote location.

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4. A system for remote monitoring of desalination plant in a cellular
telecommunication network, as substantially described herein with
reference to the accompanying drawings.

This invention relates to a system for remote monitoring of desalination plant in
a cellular telecommunication network, comprising a core module based processor
(1) comprising: means for (2,3) transmitting and receiving data through RS 232
serial communication port, a GSM modem (4) being connected to the means for
(2,3) transmitting and receiving, the processor (1) converting SMS frame
received from the GSM modem (4) into required protocol format to perform SMS
communication via the cellular network; means for (05, 06) RS-485
communication with the PLC (21) of the desalination plant over a RS-485 bus
(22), the PLC (21) communicating with modbus RTU communication ptotocol,
the processor (1) converting the modbus RTU frame into SMS frame; means for
(07) Ethernet communication (26) which serves the operating parameters of the
desalination plant (31) through a web interface; a software support structure
(16) comprising a main block (9) for initialization of the default values including
the tasks to be performed during the operation; at least two communication
driver blocks (11,13) the first driver (11) receiving and transmitting SMS protocol
based messages and/or data frames, the second driver (13) receiving and
transmitting modbus RTU protocol based data frames; at least two
communication protocol conversion blocks (10,12); and an ethernet block (14)
including an Ethernet port (15) for constructing and serving the web pages
through GPRS via the cellular network; and a device (24, 25) for interfacing the
PLC (21) of the plant (31) and the system.